Problem

For a simple table, the size-only statistics fast path looks for "type" in the table metadata. "type" is not persisted there however, so layered tables are treated as local tables. The local lookup misses and we fall back to the slow path. At high table counts this can result in OOM, as seen in BF-44448.

Definition of Done

• Layered tables successfully goes down the fast path
• The existing ASC/local-table fast path remains unchanged
• Regression tests are created

Out of Scope

• The zero checkpoint size case is tracked by WT-18119.
• The user providing a custom source.